<!DOCTYPE html>
<html lang="en">
<head>
    <script src="https://cdn.jsdelivr.net/npm/vue@2.6.12"></script>
    
</head>
<body>
    <div id="app">
        <button @click.once="add">点赞{{age}}</button>
    </div>
    <script>
        new Vue(
            {
                el:'#app',
                data:{
                    age:0
                },
            methods:{
                add:function(){
                    this.age+=1
                },
            }
            }
        )
    </script>
</body>
</html>